Technology reporters received an interesting piece of snail mail on Friday.

In neatly printed envelopes Facebook sent invitations that teased: “A small team has been working on a big idea. Join us for coffee and learn about a new product.”

On the lower right hand corner of the invite was a single coffee ring stain — but no further information about the product. They’re holding an event June 20 at 10 a.m. PST.

The low-tech invite immediately set the Internet buzzing about the potential launch of a Facebook news reader app.

Facebook, vying against the likes of Twitter and LinkedIn, is increasingly trying to become the Web’s central hub for news. Three months ago, at a recent press conference on a redesign of its news feed, Facebook’s chief Mark Zuckerberg said he wanted the company to give readers the “best personal newspaper.” And more recently, this week, Facebook announced that it was rolling out the hashtag to own more of real-time conversations.

A Facebook spokeswoman didn’t immediately respond to a request for comment.